Specifying Instructions ’ Semantics Using λ-RTL (Interim Report)

ii The Zephyr project is part of an effort to build a National Compiler Infrastructure, which will support research in compiling techniques and high-performance computing. Compilers work with source code, abstract syntax, intermediate forms, and machine instructions. By using high-level descriptions of the representations and semantics of these forms, we expect to be able to create compiler components that will be usable with different source languages, front ends, and target machines. To help deal with multiple machines, we are developing a family of Computer Systems Description Languages (CSDL) to describe properties that are relevant to the construc-tion of compilers and other systems software. The languages describe properties of a machine’s instructions or its mutable state, or both. Of particular interest is the de-scription of the semantics of instructions, i.e., their effects on the state of the machine. This report describes our design of λ-RTL, a CSDL language for specifying instructions’ semantics